Java设计模式之装饰器模式

装饰器模式结构: 
 

Component:抽象构件

ConcreteComponent:具体构件

Decorator:抽象装饰类

ConcreteDecorator:具体装饰类


UML图:

Java设计模式之装饰器模式_第1张图片


例子代码:

Java设计模式之装饰器模式_第2张图片


抽象构件

public interface Component {
    void operation1();
    void operation2();
}


具体构件

public class ConcreteComponent implements Component {

    @Override
    public void operation1() {
        System.out.println("被装饰者自带方法一");
    }

    @Override
    public void operation2() {
        System.out.println("被装饰者自带方法二");
    }
}


抽象装饰类

public abstract class Decorator implements Component{

    private Component component;

    public Decorator(Component component) {
        this.component = component;
    }

    public void operation1(){
        component.operation1();
    }

    @Override
    public void operation2() {
        component.operation2();
    }

}


具体装饰类A
public class ConcreteDecoratorA extends Decorator {

    public ConcreteDecoratorA(Component component) {
        super(component);
    }

    public void addBehavior1(){
        System.out.println("装饰器A装饰方法一");
    }

    public void addBehavior2(){
        System.out.println("装饰器A装饰方法二");
    }

    @Override
    public void operation1() {
        super.operation1();
        addBehavior1();
    }

    @Override
    public void operation2() {
        super.operation2();
        addBehavior2();
    }
}


具体装饰类B
public class ConcreteDecoratorB extends Decorator {

    public ConcreteDecoratorB(Component component) {
        super(component);
    }

    public void addBehavior1(){
        System.out.println("装饰器B装饰方法一");
    }

    public void addBehavior2(){
        System.out.println("装饰器B装饰方法二");
    }

    @Override
    public void operation1() {
        super.operation1();
        addBehavior1();
    }

    @Override
    public void operation2() {
        super.operation2();
        addBehavior2();
    }
}
客户端
public class Client {
    public static void main(String[] args) {
        Component component = new ConcreteComponent();
        Decorator decorator = new ConcreteDecoratorA(new ConcreteDecoratorB(component));
        decorator.operation1();
        decorator.operation2();
    }
}

结果打印:
Java设计模式之装饰器模式_第3张图片



你可能感兴趣的:(java设计模式,装饰器模式)